Acebutolol 3-antagonist

D. Pindolol and acebutolol antagonists with partial agonist activity... 

II Propranolol Metoprolol Nadolol Acebutolol Atenolol Pindolol Timolol Sotalol EsmoloF 3-Adrenoceptor antagonist, cardiac membrane stabilization, indirect effect on sinoatrial node to decrease rate of spontaneous diastolic depolarization. Indirect effect on A-V node to decrease conduction velocity and prolong ERR... 

There is limited evidence suggesting that celiprolol may have less adverse bronchoconstrictor effect in asthma and may even promote bronchodilation. Acebutolol is also a -selective antagonist. 

Pindolol, acebutolol, and penbutolol are partial agonists, ie, 3 blockers with some intrinsic sympathomimetic activity. They lower blood pressure by decreasing vascular resistance and appear to depress cardiac output or heart rate less than other 3 blockers, perhaps because of significantly greater agonist than antagonist effects at 32 receptors. This may be particularly beneficial for patients with... 

C. Acebutolol, atenolol, metoprolol and esmolol selective p1 antagonists... 

Acebutolol is a beta-adrenoceptor antagonist with membrane-stabilizing activity that is sometimes cited as being cardioselective but has considerable effects on bronchioles and peripheral blood vessels. 

Lipid solubility (13) determines the extent to which a drug partitions between an organic solvent and water. Propranolol, oxprenolol, metoprolol, and timolol are the most lipid-soluble beta-adrenoceptor antagonists, and atenolol, nadolol, and sotalol are the most water-soluble acebutolol and pindolol are intermediate (14). 

Adrenaline by infusion produces a transient increase in plasma potassium, followed by a prolonged fall pretreatment with beta-adrenoceptor antagonists results in a rise in plasma potassium (202). These effects may be mediated via beta2-adrenoceptors (203), and cardioselective drugs should have smaller effects (202). In the Treatment of Mild Hypertension Study (TOMHS), acebutolol did not change serum potassium after 4 years (196). 

The lupus-like syndrome was part of the practolol syndrome and has also been attributed to acebutolol (290,291), atenolol (SEDA-16, 194), labetalol (292), pindolol (293), and propranolol (294). However, apart from practolol, it seems to be very rare during treatment with beta-adrenoceptor antagonists. 

The list of beta-adrenoceptor antagonists that have been detected in breast milk includes atenolol (322), acebutolol and its active A-acetyl metabolite (323), metoprolol (324), nadolol (325), oxprenolol and timolol (326), propranolol (327), and sotalol (328). Most authors have concluded that the estimated daily infant dose derived from breastfeeding is likely to be too low to produce untoward effects in the suckling infant, and indeed such effects were not noted in the above cases. However, in the case of... 

Antagonists with similar affinity for p,-adrenoceptor and P2-adrenoceptors include nadolol, oxprenolol, propranolol and timolol whereas acebutolol, atenolol, esmolol and metoprolol show some Pi -adrenoceptor selectivity and butoxaminc is pz-adrenoceptor preferring. Labetolol, in the racemic form used in medicine, acts as both a P-adrenoceptor and an a-adrenoceptor antagonist, though these activities reside in different isomers. Further factors determining the uses of individual agents include variations... 

Beta-blockers, by inhibiting the effect of adrenaline and noradrenaline on the heart, prevent the normal increase in heart rate, and are very effective in preventing exercise angina. Examples of beta-blockers used for this purpose include acebutolol, atenolol, metoprolol. nadolol, oxprenolol, pindolol, propranolol, sotalol and timolol. See ADRENOCEPTOR ANTAGONISTS. 

Beta-blockers, of which there are many, may be used if further treatment is necessary, with or without simultaneous administration of a diuretic e.g. acebutolol, oxprenolot, propranolol and sotalol. See adrenoceptor antagonists. 

Answer D. The effectiveness of labetalol in the management of hypertension and in severe hypertensive states appears to be due to a combination of antagonistic actions at both alpha and beta adrenoceptors. Labetalol is not a P selective blocking agent (unlike atenolol and metoprolol), and (unlike pindolol and acebutolol) it lacks intrinsic sympathomimetic activity. Labetalol is available for both peroral and parenteral use unfortunately, it blocks p2 receptors in bronchiolar smooth muscle. 

Antiarrhythmics P-adrenergic antagonists acebutolol, propranolol adenosine A, agonists CVT-510... 

Mixed a antagonists phenoxybenzamine, phentolamine Pt (cardioselective) antagonists acebutolol, atenolol, esmolol, metoprolol Pj P2 (nonselective) pindolol, propranolol, timolol Oj and P antagonists carvedilol, labetalol... 

In general, beta-receptor antagonists have a detrimental effect on the serum lipid profile. Triglyceride levels are sharply increased, as are low-density lipoproteins (LDL) levels, while high-density lipoproteins (HDL) levels may be decreased. This effect is lessened, or even reversed, with drugs that have intrinsic sympathomimetic activity (e.g., pindolol, acebutolol). 

These partial agonist drugs (e.g., pindolol, acebutolol. carteolol, celiprolol, and penbu-tolol), like the beta antagonists, are useful in the therapy of hypertension and angina. They do, however, tend to cause less bradycardia and lipid abnormalities than do beta antagonist drugs. 

Acebutolol (SECTRAL, Others) is a selective (3j adrenergic receptor antagonist. The drug undergoes significant first-pass metabolism to an active metabolite, diacetolol, which accounts for most of the drug s activity. The elimination t 2 of acebutolol is 3 hours, that of diacetolol, 8—12 hours. 

Jack DB, Kendall MJ, Dean S, Laugher SJ, ZamanR, TennesonME. The effect of Itydralazine on the pharmacokinetics of three different beta adrenoceptor antagonists metoprolol, nadolol, and acebutolol. Biopharm DnigDispos (1982) 3, 47-54. 

Carazolol is a p-adrenoceptor antagonist (p-blocker) It is used for the prevention of sudden death due to stress in the transportation of pigs. Unlike most of the p-blocking agents used in human medicine such as propranolol, pindolol and acebutolol, carazolol is a carbazole derivative (Figure 13.11). 

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